Abstract: CLAIM.[.A radio pager, as shown..]. .Iadd.The ornamental design for a radio pager, as shown..Iaddend.DESCRIPTION.[.FIG. 1 is a front, top and right side perspective view of a radio pager showing our new design;.]. .Iadd.FIG. 1 is a top, front and left side perspective view of a radio pager showing our new design. .Iaddend.FIG. 2 is a front elevational view thereof;FIG. 3 is a rear elevational view thereof;FIG. 4 is a top plan view thereof;FIG. 5 is a bottom plan view thereof;FIG. 6 is a left side elevational view thereof; and,FIG. 7 is a right side elevational view thereof.